Considerations about the effectiveness and cost effectiveness of therapies in the treatment of hyperphosphataemia

Because of an elevated serum phosphate level, patients who suffer from chronic kidney failure frequently tend to have cardiovascular calcification and are therefore exposed to a higher probability of a fatal event. Phosphate binders are able to reduce these negative effects. Currently, there are primarily two groups of phosphate binders (calcium-containing and calcium-free phosphate binders) which are considered to be almost equally effective in terms of binding of free phosphate. There are, however, a few disadvantages of the two groups. While the calcium-containing binders are associated with an increased risk of hypercalcemia, which is dose dependent, calcium-free binders have been criticized as being too expensive. As the expenditure for patients suffering from chronic kidney failure increases from year to year, as a result of increasing prevalence, there is a growing need for an alternative to existing phosphate binders. The study presented here therefore summarizes available information for the novel combination preparation OsvaRen ® (calcium acetate/magnesium carbonate) as an alternative therapy to the calcium-free phosphate binder Renagel ® (sevelamer-hydrochloride) and to calcium-containing preparations. The results of this systematic review showed that OsvaRen ® is at least equally effective in the regulation of serum phosphate level as Renagel ® . In particular, OsvaRen ® shows no clinically relevant difference in terms of the control of the serum calcium levels compared to Renagel ® and thereby does not increase the risk of a hypercalcaemia, in contrast to pure calcium-based phosphate binders. On the other hand, Renagel ® therapy is much more frequently associated with gastrointestinal side-effects, a tendency to result in higher tablet burden for patients and high medication costs. The CALMAG study showed that OsvaRen ® was at least as effective and safe in terms of controlling serum phosphate and serum calcium levels as Renagel ® while, at the same time, resulting in about 80% lower costs. In addition, OsvaRen ® offers a lower risk of hypercalcaemia and associated subsequent costs and is thereby also superior to pure calcium-containing phosphate binders. Because of the effectiveness and tolerability of calcium acetate/magnesium carbonate, OsvaRen ® offers a clinically suitable and, at the same time, cost-effective therapeutic option in the therapy of hyperphosphataemia. Copyright Prenzler et al; licensee Springer. 2011